Abstract:
The thermal shock resistance of FeAl/Al
2O
3, FeCrAl/Al
2O
3, FeAl/Al
2O
3-13%TiO
2, and FeCrAl/Al
2O
3-13%TiO
2 coatings deposited by supersonic atmospheric plasma spraying (SAPS) on the stainless steel matrix was investigated in this paper. The microstructure of the coatings was characterized by scanning electron microscope, the porosity was measured by image analysis, the mass fraction of α-Al
2O
3 was calculated by multi peak method, and the bonding strength was tested. The results show that, the mass fraction of α-Al
2O
3 in Al
2O
3 coating is 40.3%~42.5%, the porosity is 3.47%~3.52%; the mass fraction of α-Al
2O
3 in Al
2O
3-13%TiO
2 coating is about 24.0%~29.7%, the porosity is 3.12%~3.31%. The results of water-quenching tests at 800 ℃ for 30 min show that, the FeCrAl/Al
2O
3 coating presents the highest thermal shock resistance, and the FeCrAl/Al
2O
3-13%TiO
2 coating takes the second place. The FeAl/Al
2O
3 and FeAl/Al
2O
3-13%TiO
2 coatings exhibite the same thermal shock resistance, which are the worst in four kinds of coatings.